Monster Machines: This Clever Egg Washer Could Save 90 Million Chickens A Year

Dr. Craig Coufal, left, a Texas A&M AgriLife Extension Service poultry specialist and assistant professor the Department of Poultry Science, examines the second-generation egg-sanitizing machine built from his design by a local College Station fabricator. (Texas A&M AgriLife Extension Service photo by Robert Burns)

Regardless of which came first, chickens and their eggs are big business. The problem is eggs have a natural failure rate (due to bacterial infections and such) of 1 per cent — 90 million birds annually in the US alone — and the best methods of cleaning the eggs leaves them more exposed to infection. But this prototype egg sanitizer from Texas A&M could save a lot of soon-to-be chicks from early termination.

When an egg exits the hen, it’s coated with a waxy protective cuticle. This coating prevents bacterial infections for the first week or so (the most critical time for an embryo) by clogging the shell’s pores. The coating later wears off to facilitate gas exchange, allowing the developing chick to breathe. But in industrialized chicken propagation, newly laid eggs are often bathed in a hot (43C-49C) detergent wash that strips this coating, leaving the embryo exposed to all sorts of infection. Seriously, you ever see inside an industrial hen house? It’s filthy. Even getting eggs wet after washing is enough to significantly increase the number of bad eggs.

So rather than scrub off the cuticle along with the bacteria, Dr Craig Coufal, a poultry specialist with Texas A&M AgriLife Extension Service and assistant professor the Department of Poultry Science, and his team created an egg sanitizer that does away with the detergent altogether. Instead, Coufal’s washer relies on hydrogen peroxide and UV light to clean them. Eggs are first doused in a fine mist of hydrogen peroxide, then exposed to the UV light. The hydrogen peroxide interacts with the UV rays to generate hydroxyl ions, which kill germs without disintegrating the cuticle.

Early lab tests are extremely promising, with zero chemical residue, no change to the yolk’s texture or taste (as 49C detergent baths are wont to do), and low secondary infection rates, thanks to the intact cuticle. The machine is still in the prototype stage but Coufal’s team is working to install a pilot machine in a local hatchery in the coming months. [via Gizmodo]